Early Singing Insects

by Carl Strang

To this point in the season I have heard singing males of 10 insect species in northeast Illinois. All but one began earlier than in any of the years from 2006 to 2011. This is consistent with more general insect phenology this year, and is attributable to a mild winter and a warm March which heated the soil earlier than usual. The only species with a later starting date was the spring field cricket, a species I usually hear first while running or bike riding, activities my back trouble prevented during the critical time period. And yet, despite that limited mobility, I have recorded dates for the other 9 species that ranged 5-22 days earlier than in any previous year (4 of the previous records were in 2007, 5 in 2010, 1 last year; they add up to 10 because of a tie). The only other case perhaps worth singling out was the broad-winged bush katydid, 22 days earlier than last year’s previous record. This species is not abundant or widely distributed, and I suspect it has a longer, earlier season than I have realized before. I should make some effort in future years to get a better handle on its starting and ending dates.

Broad-winged bush katydid

For those who may be interested, here are all the first song dates this year so far. Greenstriped grasshopper 3 April, 17 days earlier than the previous record. Spring field cricket 25 May, 20 days later. Roesel’s katydid 29 May, 11 days earlier. Protean shieldback 5 June, 7 days earlier. Linne’s cicada 14 June, 12 days earlier. Gladiator meadow katydid 14 June, 7 days earlier. Dog day cicada 15 June, 5 days earlier. Scissor-grinder cicada 19 June, 13 days earlier. Broad-winged bush katydid 23 June, 22 days earlier. Lyric cicada 24 June, 6 days earlier.

Advertisements

Roesel’s Katydid in Michigan

by Carl Strang

In recent years, collaboration between Scott Namestnik and I, augmented by observations from several others, has resulted in a much improved understanding of the range of Roesel’s katydid, a European import which has spread from Quebec through a large area of SE Canada and the northeastern U.S. We have connected the northeastern katydids to those in Indiana and Illinois, and miscellaneous other observations have documented the insect in Iowa and Wisconsin. Here is the current map from the Singing Insects of North America (SINA) website.

The current map for Roesel’s katydid in SINA.

As you can see, the Lower Peninsula of Michigan is a gaping hole in the species’ range, which didn’t make sense, so this year we resolved to do some searching there. Scott struck first, finding Roesel’s in Kalamazoo County. A goal of my trip into Michigan last week was to look for Roesel’s farther north. Thursday was cool and rainy, and I didn’t have much luck. However, after moving into my room at the Grayling Ramada I went for a short walk in the wooded area behind (west of) the motel, and was surprised to hear a few late afternoon buzzes that to my ear were identical to Roesel’s. They were in an open woodland with ground cover dominated by bracken.

Part of the area with possible Roesel’s.

I also heard a crepitating grasshopper that I thought might be the greenstriped, and a stridulating grasshopper that probably would be new to me. The next day, after the Kirtland’s warbler tour, I returned, but the weather was cool and the possible Roesel’s were singing only at great intervals. I never got a look at one, though I photographed a couple grasshoppers. The crepitating one indeed was the greenstriped.

This one landed on the parking lot and posed.

The only other mature grasshopper species I was able to see had long wings and probably does not stridulate.

My best guess at an identification is that this is the little pasture grasshopper, an early season species that has a broad habitat range.

I couldn’t wait around on the off chance that things would warm significantly. My identification of Roesel’s is likely but not certain. The only other singing insects with a buzz remotely like that of Roesel’s are some of the coneheads, but they are much louder and later in the season. Unless there is something I don’t know about, these should in time prove to be Roesel’s. I shifted south, to the State Road 46 region. This area is just south of the forests and marshes that dominate the northern part of the Lower Peninsula. I stopped in the little village of Elwell, parking at an access point for the Fred Meijer Heartland Trail. I walked the trail back east a mile.

Fred Meijer Heartland Trail

I heard no Roesel’s on the way out. The trail intersected Rich Road, which looked promising, and indeed I found several Roesel’s singing just south of the trail crossing.

Rich Road proved rich indeed for my target insect.

I got looks at 2, one a short-winged variant and one either long-winged or mid-length.

I wasn’t able to photograph any of the Michigan Roesel’s. Here is a long-winged one in Illinois.

The only insect I photographed there was an obliging bronze copper.

This butterfly occurs in DuPage County, too, but is not particularly common.

On the way back to the car I found a long-winged Roesel’s singing along the trail. So, we have confirmed them in southwest and mid-central Lower Michigan, with likely ones at Grayling as well. That hole in the katydid’s range is, as we expected, at least partially filled.

The SINA map showing the three locations mentioned here.

That concludes my research on this particular question, at least for now.

Kirtland’s Warbler Tour

by Carl Strang

Last Thursday and Friday I drove into the northern part of Michigan’s Lower Peninsula. I had two goals, the first of which I’ll detail tomorrow. My secondary goal was to take the Kirtland’s warbler tour. This is a seasonal education opportunity offered by the U.S. Fish & Wildlife Service and Michigan Audubon (nearly done for this year). The tours begin with a video introduction at the Ramada in Grayling, and then the guide leads participants in a car caravan to the tour site. We drove to an area where the current crop of jack pines was mainly 3-5 feet tall.

The pines are on a harvest rotation, with large areas clear-cut and replanted, so that there always are large areas covered with the small pines the warblers favor.

Kirtland’s warbler is a federally endangered species, but the population trend is upward and the range is expanding thanks to the intense management efforts. Now some are breeding in Wisconsin and Ontario as well as both peninsulas of Michigan. The rarity of the species draws birders to the area, and about 15 of us were on the Friday morning tour.

Allison, our guide, was knowledgeable, and there were plenty of competent birders in the group to assist with the spotting.

The area appears to be structurally and botanically fairly simple. The pines were dominant in the area, with scattered oaks and cherries the other large woody plants.

Jack pine has short needles and small, curved cones.

Between the pines were a few shrubs, mainly huckleberries or blueberries, as well as sweetfern, one of my favorites.

The wonderful odor of sweetfern leaves I associate with wild places. Sadly it does not occur in DuPage County, as it is a sandy soil species.

Among the herbaceous plants were scattered hairy puccoons.

This is another sandy soil plant.

The puccoons frequently threw off some of the more anxious birders whose search image was tuned to the color yellow. Kirtland’s warbler males were singing loudly at all times, but for a while they stayed out of sight. In the meantime we enjoyed a surprising diversity of birds for such a simple ecosystem: four sparrows (field, vesper, clay-colored, Lincoln’s), 3 warblers (Kirtland’s, Nashville, palm), nighthawk, upland sandpiper, brown thrasher, towhee, Brewer’s blackbird, and rose-breasted grosbeak were notable ones. Eventually a male Kirtland’s warbler perched and sang on an exposed branch.

This is an expanded view of the dot on my photo that represented the warbler. We had good spotting scope views.

The tour was highly satisfying. However, it did not allow me to further my primary goal, which was to find Roesel’s katydids in the Lower Peninsula. More on that tomorrow.

Growing the Plant List

by Carl Strang

As I continue to wander off-trail through all the ecosystems at Mayslake Forest Preserve, I continue to find new plant species. The preserve’s list of herbaceous plants now numbers 308 species, and woody plants are at 90 (though some of these are exotic trees planted on or near the mansion grounds). Some of the new finds are few in number and less conspicuous than others.

Honewort has tiny white flowers. I did not find this one until I was on top of it.

Though not conspicuous, honewort at least is easy to identify.

The uneven umbel of flowers, and the distinctive leaf shape, make this woodland plant distinctive.

The next species stands out more, but apparently there are only a very few, seeded in an earlier stage of prairie restoration.

Prairie coreopsis, the third species of its genus I have found at Mayslake.

Again, the leaves help to distinguish this plant from its relatives.

The stiff little leaves all are identical and 3-lobed.

A small colony of pineapple weed has become established in a sunny bit of trail near May’s Lake.

Named for the odor of its bruised foliage, this western species of rayless composite does well in dry, compacted soils.

I was pleased to find a green dragon that earlier had been discovered by the restoration volunteers.

Though growing in a relatively dry location, this one was doing well enough that it elected to be female this season.

Apparently this is the only green dragon on the preserve, and Mayslake is the only preserve that has green dragon but not its more common close relative, the jack-in-the-pulpit.

I will close with two plants which, while not new discoveries, struck me with their beauty. One of these was a sedge, the small yellow fox sedge, which I had identified last year but not followed after it was done flowering.

The ripened perigynia are such a bright yellow that I wonder whether this plant uses birds to disperse its seeds.

Finally, it is easy to dismiss self heal, but some individuals of this familiar plant of disturbed woodlands really display beautiful, if small flowers.

The native subspecies is generally taller than the introduced lawn version.

There can be no doubt that this 90-acre preserve still has botanical secrets to be discovered.

Spring Field Cricket Observations

by Carl Strang

There are indications that the season for spring field crickets is winding down. That is not surprising, given the early start that this year has given to insects, but it means suspending my driving survey until the fall field crickets are singing. I was able to cover a large part of western DuPage County in the time I had, though, and I was able to make some observations.

Only rarely were spring field crickets to be found away from areas dense with tall grasses.

Thus forest preserves, railroad corridors and some highway corridors were the most consistent places where I heard spring field crickets singing, and all high-density clusters of the insects were in such locations. That is not to say, however, that all fields with tall grasses had crickets.

One obvious example is the friary site at Mayslake Forest Preserve, which was bare soil until recently seeded with grasses.

History appears to be important here. Spring field crickets would seem to have limited dispersal ability, and local extinction is not readily followed by new invasion unless a source population is really close. This gives an inkling of what may differentiate the spring and fall field crickets. Spring field crickets overwinter as relatively vulnerable nymphs, and need more robust shelter from severe winter conditions. Fall field crickets overwinter as eggs, relatively safe as they are buried in the soil. This allows them to live in a wider variety of places, and makes them less susceptible to local extinction. At least now I have a hypothesis to work with.

Carex Confusion

by Carl Strang

Last year it seemed so easy. I began studying the sedges, grasses and similar plants at Mayslake Forest Preserve, and for the most part had an easier time than expected. This year I am continuing to find new sedges, but the most recent ones are giving me more trouble. All three are growing in Mayslake’s woodlands, which I call savannas but which technically have an oak stem density between savanna and forest levels. The first of these sedges is growing mainly vegetatively.

A strip along the west edge of the north savanna above the stream is dominated by the leaves of this sedge, but few of the plants are flowering.

A number of fruiting stalks at one end of the strip provided material for identification, and after wrestling with the key and some on-line references I decided they were Carex normalis.

Carex normalis, the spreading oval sedge, is similar to another species I have found at Mayslake, C. molesta. One difference is that normalis has more spikelets per flowering stalk.

The next one I feel less certain about, although the key seems to point only to one species, the fescue oval sedge (C. festucacia).

This one is growing on a drier site on the slope of the south savanna.

The spikelets have an odd spacing.

The habitat is right for festucacia, but it is described as uncommon.

The third species, growing close to the previous one, I simply cannot identify. One would think that with dozens of species of Carex in our area, it should be possible to find a match, but no dice. It is a single plant, and perhaps it simply is anomalous.

The most striking feature is that most inflorescences are composed entirely of male spikelets.

Others have several female spikelets and a single male one at the tip.

This is perhaps the best example on that plant.

Already the female spikelets are coming apart, perhaps an indication that this plant bloomed early.

It looks like there originally were more spikelets on this stem.

The leaves are relatively narrow.

Clearly this is a tufted species.

While I welcome any help readers can provide on this, my best bet is to catch these plants earlier next year, when they are flowering, and try again.

Bored

by Carl Strang

The emerald ash borer has become a common tree-killer in northeast Illinois. I knew it was likely that, sooner or later, the green ash in my front yard would become infested, and now it has happened. My tree held out longer than most of the ashes in my subdivision, but it was on the decline before the borers came along, and now the symptoms are clear.

The top branches are dying, and the tree is responding by producing a dense growth of lower shoots (only a small part of that bunch of green is the tree’s Virginia creeper vine). This is a typical pattern, as the beetles lay eggs in the top of the tree first.

I haven’t yet seen the diagnostic D-shaped exit holes made by emerging adults of these bark beetles, but one of the lower dying branches had several woodpecker holes which are a further clue.

There were a number of holes just like this one, made by a woodpecker extracting a larva.

So, sometime within the next few months I’ll have to have the ash removed, and I am contemplating what kind of tree to put in its place.

The Photogenic Sumacs

by Carl Strang

(Note: this entry first was posted as a Nature Note on the Forest Preserve District of DuPage County’s Observe Your Preserve website). Staghorn sumacs are in bloom, and as I lined up the camera on a pyramid of male flowers it occurred to me that this is a relatively photogenic plant for a good part of the year.

The sun speckles diminish this photo, but not the interesting shape of the inflorescence.

These shrubs expand through the roots, and have the genders separated on different plants, so that a given cluster is in fact a male or female clone colony.

Female flower clusters likewise have a pyramidal shape, but develop into fuzzy bright red fruits that contrast against the green compound leaves.

Autumn brings change to the sumac, the leaves showing brilliant reds and oranges unmatched by our other woody plants.

Isolated stems stand out.

Larger colonies collectively form a pyramid, the taller older plants in the middle and their progressively younger, shorter offshoots arrayed in concentric rings outward.

These examples all are from Mayslake Forest Preserve.

Though staghorn sumacs are featured here, the same comments would apply to the smooth sumac. The latter species is similar, but has stems that are smooth rather than hairy like those of staghorn sumac. The smooth sumac is more adapted to prairies, and historically is regarded as more clearly native to DuPage County. The staghorn sumac may or may not be native to the county, but if not it spread from populations a little farther east. (Note: In an interesting coincidence, yesterday after posting this as a Nature Note, I found a male colony of smooth sumac at Mayslake, so both species are there.)

Back to the Friary Site

by Carl Strang

Recently I went back up to the site of the former friary at Mayslake Forest Preserve. Late last year abundant, lawn-like grasses had sprouted abundantly around the edges, and I was curious as to what they might be.

They looked like this in the autumn.

They had indeed grown tall and begun to flower.

The site looked like this on May 29.

I hadn’t really expected them to be prairie grasses. They proved to be a soil-holding temporary fill-in, the Italian rye grass.

This is a taller, coarser relative of the smaller rye grass commonly included in lawn mixes.

Otherwise, the area continues to be dominated by weeds. One that is a personal guilty pleasure is the squirrel-tail grass.

Yes, it is a weed, but I think it’s beautiful. Also it has a bouncy name: Hordeum jubatum. Jubilation is a word that comes to mind when the wind combs this grass.

I look forward to the eventual incursion of prairie and savanna plants.

Odonata Appearances

by Carl Strang

Additional insect species continue to make their first appearances of the year at Mayslake Forest Preserve. Last week brought the first widow skimmer.

This is a teneral, or newly emerged, individual. Note the faint undeveloped dark wing areas.

I remember learning to recognize these years ago, finally releasing my focus on wing pattern as I discovered the suspenders-like yellow body striping.

I still haven’t internalized the differences among spreadwing damselflies, and try to photograph every one I see.

Females like this slender spreadwing I find particularly challenging. The pale wingtip veins are a big help here.

One fun photographic challenge is to get pictures of dragonflies in flight.

Some, like the prince baskettail, never seem to land, so flight photos are the only choice most of the time.

Though insects continue to appear early, there are plenty still to emerge as the season is yet young.

« Older entries

%d bloggers like this: